Automatic stirrer



L- W. KAUFMAN AUTOMATIC STIRRER July 2 1968 2 Sheets-Sheet 1 Filed June 19,: 1967 INVENTOR Louis W. Kaufman BY wg db AGENT WITNESSES My 2, 963 L. w. KAUFMAN AUTOMATIC STIRRER Fi led June 19, 1967 2 Sheets-Sheet 2 United States Patent i O 3,390,868 AUTOMATIC STIRRER Louis W. Kaufman, Mansfield, Ohio, assignor to Westinghouse Electric Corporation, Pittsburgh, Pa., a corporation of Pennsylvania Filed June 19, 1967, Ser. No. 647,052 9 Claims. (Cl. 259-138) ABSTRACT OF THE DISCLOSURE A wire form stirrer structure adapted for automatic rotation within a cooking vessel. The wire form is supported on a hub member by a pivot which is carried by the hub member at a point removed from its axis of rotation thereby producing oscillatory as well as rotational movement of the wire form in response to rotation of the hub member.

Background of the invention This invention relates, in general, to automatic stirring apparatus and, more particularly, to agitator structure for use therewith.

Automatic stirrers comprising a rotatable hub and an integral agitator supported concentrically with respect thereto have, heretofore, been utilized for the purpose of mixing liquids as well as other substances. A magnet or other coupling means adapted to be rotated by a suitable motor is supported beneath a non-magnetic container or vessel in which the foregoing agitator is supported for rotation. When the consistency of the substance being mixed remains constant, the above-described arrangement works quite well, however, it is not totally satisfactory when the substance becomes very viscous.

The operation of the foregoing stirring structure has been improved by providing a hub member having a pivot member disposed thereon at a point remote or olfset from the center of rotation of the hub member. The agitator is mounted on the hub for rotation therewith by interconnecting means which frictionally engages the pivot member such that the agitator is capable of rotating with and/or oscillating relative thereto.

Heretofore, in order to accommodate containers or vessels of different sizes it has been necessary to provide agitators of different sizes, one for each size vessel or container.

Objects Accordingly, his the general object of this invention to provide new and improved stirring apparatus.

It is a more particular object of this invention to provide a new and improved agitator structure.

Another object of this invention is to provide new and improved agitator structure which will accommodate containers or vessels of diiferent sizes without the requirement for additional agitators of different sizes.

Summary Briefly, the present invention accomplishes the abovecited objects by providing a hub member adapted for rotation within a cooking vessel. The hub member carries on the upper surface thereof a pivot in the form of a post member which is disposed at a point remote from the axis of rotation of the hub. Agitator structure fabricated from a single piece of wire form is bent into a plurality of segments two of which cooperate to form an elongated recess comprising a bight area and a plurality of enlarged areas. The post member is received in the recess and is frictionally engaged and retained in one of the enlarged areas by the segments forming the recess. Each of the enlarged areas in which the post member may be received will enable the agitator structure to be used in one size pot or another depending on the position of the enlarged area relative to the longitudinal axis of the recess. Further objects and advantages of the present invention will become more apparent when considered in view of the following detailed description and drawings.

Description of the drawings Referring now to the drawings, especially FIGS. 1 and 2, reference character 10 designates generally agitator structure adapted to be supported for movement with a hub member 1 1. The agitator or arm structure 10, made from any suitable material, for example, a single piece of steel wire, is bent or otherwise suitably shaped into a form continuous segmented structure suitable for mixing the contents of a vessel or container 12.

In the form of the invention illustrated, the hub member 11 comprises a permanent magnet covered with suitable material, for example, nylon. A permannet magnet 13 secured to a shaft 14 of a motor 16 (shown schematically in FIG. 2) is adapted to be supported subadjacent the container 12 directly below the hub member 11. The proximity of the two magnets provides a magnetic coupling therebetween serving to produce rotation of the hub'member 11 with the magnet 13 when the latter is rotated by the motor 16 through the shaft 14. The container 12, made from any non-magnetic material, for example, aluminum, is supported on an electric heater structure 17 comprising a plurality of conventional coils 18. Thus, it can be seen that automatic stirring while cooking can be accomplished with the present invention.

The arm structure 10, which is adapted to rotate in the same or counterclockwise direction with the hub member 11 in a manner to be described hereinafter, comprises a pair of similarly shaped arms 19 (best illustrated in FIG. 1), each having a substantially vertical leading segment 22 and an offset trailing segment 23 joined by a horizontally disposed spiral segment 24. Each of the offset segments 23 comprises a vertical component 26 and a horizontal component 27.

The components 27 are interconnected by a pair of resilient segments 28 forming a spring-like clip 30, delineating an elongated recess 29. The segments 28 are deformed or curved as indicated at 30 and 31 to form enlarged areas 32 and 33 for receiving a post or pivot member 34 in a manner to be described hereinafter. An arcuate bight portion 35 formed by the segments 28 is of sufficient radius so as to permit insertion of ones finger to facilitate mounting of the agitator 10 on the hub member 11.

Substantially V-shaped handle means 36 including a grip member 37 interconnects the arms 19 at the upper portion of the verticle leading segments 22 and together with the segments 22, 23, 24, 2 7 and 28 form an integral or unitary agitator 10.

The post member 34 is secured to a top surface or wall 38 of the hub member 11 with its longitudinal axis disposed parallel to but remote from the axis of rotation of the hub member. The post member 34 comprises a tenon portion 39 (see FIG. 2) adjacent its lower extremity and a substantially cone-shaped top 40. A necked-down portion 41 of the post member disposed intermediate the tenon 39 and the head or top 40 is insertable into either of the enlarged areas 32 or 33 through the open end of the recess 29. The segments 28 are resilient and the space therebetween, in an unstressed condition, at the areas 32 and 33 is less than the diameter of the necked-down portion 41, accordingly, When the post member 34 is inserted the segments 28 are stressed. It will, therefore, be appreciated that the restoring force in the resilient segments 28 causes them to frictionally engage the necked-down portion 41 thereby coupling the agitator '10, to the hub member 11 for rotation therewith. It will further be appreciated that as the viscosity of the contents of the vessel 12 increase due to application of heat, a resistance to rotation of the arm structure is developed thereby causing relative slippage between the segments 28 and the neckeddown portion 41. At this point the hub continues to rotate and due to the position of the pivot member 32 relative to the axis of rotation of the hub member 11, oscillatory motion toward and away from the center of rotation of the hub member 11, as shown in FIGS. 3 and 4, is imparted to the agitator 10. The path of movement will be apparent from noting the successive positions occupied by the spiral-shaped segments 24.

As can be seen from FIG. 3, the degree of oscillation of the agitator 10 is substantially less than the magnitude of oscillation of the agitator of FIG. 4 in which the post member 34 is received in the enlarged opening 33 while in FIG. 3 the post member 34 is received in the enlarged area 32. For purposes of illustration and to show the difference in degree of oscillation the agitator structure 10 has been illustrated in a vessel 12 in both FIGS. 3 and 4, the vessel 12 being the same size in each figure. It should be apparent that when the post 34 is received in the recess 32. as shown in FIG. 3 the agitator structure may be used in a somewhat smaller vessel than actually shown. It should be further apparent that the relative positioning of the agitator structure 10 and the hub member 11 as shown in FIG. 4, therefore, the post member 34 being received in the recess 33, that the container 12 is the proper size.

As can be seen in FIG. 2, the hub 11 is provided with a somewhat rounded bottom surface 42 which permits the agitator structure 10 to rock slightly thereby enhancing its stirring capabilities.

Since numerous changes may be made in the above described apparatus and different embodiments of the invention may be made without departing from the spirit thereof, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is: 1. In combination, segmented stirring means for agitating the contents of a vessel, means for supporting said stirring means in said vessel, said means being adapted for rotation in said vessel, said stirring means comprising a segmented structure including a recess formed by a pair of segments thereof, interconnecting means carried by said support means and insertable into said recess for operatively coupling said stirring means and said support means, said recess forming segments being adapted to engage said interconnecting means at a plurality of positions along the longitudinal axis of said recess.

2. Structure as specified in claim -1, wherein said segments cooperate to form a spring clip structure delineating said recess.

3. Structure as specified in claim 2, wherein said recess deformed segments comprise at least two pairs of opposed deformed areas disposed along the longitudinal axis of said recess and an arcuate portion comprising one end of said recess.

4. Structure as specified in claim 3, wherein said arcuate portion is of sufiicient size for insertion of a finger within said recess for facilitating the mounting of said stirring means on said support means.

5. Structure as specified in claim 1, wherein said means carried by said support means is positioned at a point remote from the center of rotation of said support means, and said segments and said means received in said recess are adapted for intermittent relative rotation and simultaneous movement whereby oscillatory motion is imparted to said stirring means when there is relative rotation between said segments and said means carried by said support means.

6. Structure as specified in claim 5, wherein said segments cooperate to form a spring-like clip defining said recess.

7. Structure as specified in claim 6, wherein said recess defining segments comprise at least two pairs of opposed deformed areas disposed along the longitudinal axis of said recess and an arcuate portion forming one end of said recess.

8. Structure as specified in claim 7, wherein said arcuate portion is of sufiicient size for insertion of a finger into said recess for facilitating insertion of said means carried by said support means into said recess.

9. Structure as specified in claim 1, wherein said segmented structure comprises a continuous wire form.

References Cited UNITED STATES PATENTS 789,172 5/1905 Roeck 259- 1,949,047 2/1934 Hill 259-135 2,034,214 3/1936 Smith 259134 2,571,316 10/1951 Guilder '259129 X 3,245,665 4/1966 Steel 259108 X ROBERT W. JENKINS, Primary Examiner. 

